Italian football legend Gianluca Vialli has been impressed by the "unbelievable" fitness of Gaelic footballers.
The former World Footballer of the Year, who is managing Erin's Isle as part of AIB's The Toughest Rivalry series, says GAA players require an all-round fitness to cover the ground, even with 15 men on the field.
"You need to be unbelievably fit for Gaelic football," said Vialli.
"The pitch is huge, it looks like an airport to me! And there are not that many players to cover it so it really is a physical game with a lot of physical contact and the pace of the game is very fast and furious.
"Tactically it is also very different and you need to be an all-rounder.
"You need to be fast but able to run for 60 to 70 minutes so it's like sprinting continuously. You need to able to take the blows, need to be courageous and pass the ball with your feet and fist so it really takes a lot of skill to play this game."
The amateur ethos reminds him of his time as a youth footballer in Italy.
"It is quite rare that you see guys playing a game just for the passion of the game, without being paid, just for the love of it and representing their parish.
"All of this was new to me and reminded me of where I started in football, in the oratory system in Italy, but I was fascinated to find out more about it bit by bit.
"It grew into me very quickly."